Jedi VHF/AIS station design

[s/v Jedi]

Originally Posted by S/V Illusion

A testament to the practice of using true grounded switches grounding both ‘sides’ of the coax. Everything else is questionable window dressing.

This is what the Daiwa switch does, as long as you make sure it is grounded of course.

Second part of the switch is that it puts a 50 Ohm dummy load on the transceiver antenna port, which blocks any static buildup there as well.

[s/v Jedi]

I have been considering all the comments that came in both in-thread as well as by pm and decided to alter the following:

I had recommended to replace the coax coupler you have where the coax cable enters the boat from the mast with a surge suppressor.

This really is the ideal location for it because a properly bonded mast has the grounding plate very near and you must always strive to bring the surge suppression as close to this point (and as far away from the radio) as possible.

I am adding a specific recommendation for which suppressor, which was suggested to me by a friend and after studying their website, it appears to be the perfect product with perfect company, offering many different types incl. different connectors and even replacement parts like gas discharge tubes etc.

I have attached a photo as well as the diagram of this suppressor. Here is the link to this product again: https://www.arraysolutions.com/as-30...mME9sIzN_gtgoI

(I have no contact/ benefit from any product I recommend)

For the diagram I posted in this thread, I keep everything the same. This is to be installed as close to the radio as possible and provides all the benefits discussed earlier.

Remember that good surge protection has multiple tiers. Normally, for houses, there are three levels of surge protection for grid power: first right at the entry of the utility cable. This is the big whole house suppressor that I installed outdoors at the electrical box where the cable from Florida Power enters.
The second level is in the breaker box where all the branch circuits form. These suppressors look just like a breaker and fit in a position (for a 240V breaker for a US installation).
The third level is at each individual appliance. You have outlets with surge suppressors, small UPS’s, or even simple power strips that include a suppressor.

For coax there are no branch circuits so levels one and three are left, which is implemented with this setup. The suppressor at the base of the mast takes the big hit, possibly self sacrificing parts of itself in the process, while the small suppressor at the coax switch deals with whatever is left over and should never reach the point of needing to self sacrifice itself.

[captNordy]

Jedi - Thanks as always for your work on these topics. It helps me tremendously. I am in the process of working on my VHF as I have a weak signal and came across this which also helps with another of my projects; assuring bonding is correct for lightning. I have a couple of questions, if I may:

1. on my 48' boat my boding wire from the mast attaches to a bolt that is embedded in fiberglass, directly beneath the mast. Presumably this is a bolt that goes down to the keel. Can I use this bolt in place of the dynaplate you have in your diagram (attaching Coaxial supressor, chainplate bonding, etc.)?
2. You mention this being a good time to add both DC and AC surge supressors. I do not have those in my system currently. Can you point me to any products/threads/etc. so I can learn more about these and where they fit in?

Thanks so much!

[s/v Jedi]

Originally Posted by captNordy

Jedi - Thanks as always for your work on these topics. It helps me tremendously. I am in the process of working on my VHF as I have a weak signal and came across this which also helps with another of my projects; assuring bonding is correct for lightning. I have a couple of questions, if I may:

1. on my 48' boat my boding wire from the mast attaches to a bolt that is embedded in fiberglass, directly beneath the mast. Presumably this is a bolt that goes down to the keel. Can I use this bolt in place of the dynaplate you have in your diagram (attaching Coaxial supressor, chainplate bonding, etc.)?
2. You mention this being a good time to add both DC and AC surge supressors. I do not have those in my system currently. Can you point me to any products/threads/etc. so I can learn more about these and where they fit in?

Thanks so much!

Yes, that bolt will do but to prevent damage from small surges, I would want the metal that this bolt connects to (lead keel?) to be in contact with the water. So not covered by antifouling like for a keel.

The reason is that a small surge will not be able to punch through the paint and it won’t work.

But there may be more bonding wires incl. to the propshaft, thru hull fittings etc.

For lightning protection. I have a thread that shows general DC suppression as well as a hardened power supply for electronics (I have since removed the VHF radio from that setup). That thread is here: https://www.cruisersforum.com/forums...cs-270317.html

The suppressors used there are these: https://www.amazon.com/gp/product/B09KBRXXXR

For A/C I didn’t post recently so I lost my thread from many years ago, but I use this suppressor at the shore power inlet:
https://www.amazon.com/Square-Schnei.../dp/B00CONA1OQ

If you have a lot of lightning around but like to use the big 12kW US shore power 120/240V 50A then I recommend this unit which is also a management system that will only pass good power: https://www.amazon.com/gp/product/B003AN1UA8
(It has a contactor). I have that as well for use at our marina slip in Florida. There’s a thread about that as well.

I also recommend another AC surge suppressor at the AC distribution panel. That is called the level 2 protection. It handles whatever is left over after the suppressor at the shore power inlet does most of the work there, but in addition, it handles surges coming from branche circuits when a surge comes from appliances like A/C units, refrigerators etc. either by their normal operation or when exposed to a near lightning strike.

There’s also a level 3. This would be a power outlet or power strip with a built in suppressor. Or even these small APC UPS units. You would use those for electronics like TV’s, computers etc.

[s/v Jedi]

I did some digging and found pictures. It shows the 120/240V shore power management and surge suppression module mentioned earlier installed. Also, there is a 50A galvanic isolator from Yandina in that circuit.

The DIN rail box has the primary breakers for two shore power connections, the generator and the secondary winding of the isolation transformer. It also has some terminals for ground wiring.

The last picture shows a popular way of coax surge suppression, where you mount a copper ground bar that the suppressors are bolted onto. These are normally installed where coax cables enter buildings.

[captNordy]

Originally Posted by s/v Jedi

Yes, that bolt will do but to prevent damage from small surges, I would want the metal that this bolt connects to (lead keel?) to be in contact with the water. So not covered by antifouling like for a keel.

The reason is that a small surge will not be able to punch through the paint and it won’t work.

But there may be more bonding wires incl. to the propshaft, thru hull fittings etc.

Yes, there is another bolt coming out of fiberglass where the prop shaft enters the engine room. Presumably, the aft thru hulls, diesel tank, etc. link to this bonding bolt, and the fwd thru hulls, water tanks, mast and chainplates rout through the bolt at the mast base.


I will verify all this with continuity meters. However, you mention only having chainplates, mast, and coax surge on the fwd bonding bolt, but that would then mean a long cable run for the fwd thru hulls, and water tanks back to the rear bonding bolt, which is not ideal...

Originally Posted by s/v Jedi

For lightning protection. I have a thread that shows general DC suppression as well as a hardened power supply for electronics (I have since removed the VHF radio from that setup). That thread is here: https://www.cruisersforum.com/forums...cs-270317.html

The suppressors used there are these: https://www.amazon.com/gp/product/B09KBRXXXR

For A/C I didn’t post recently so I lost my thread from many years ago, but I use this suppressor at the shore power inlet:
https://www.amazon.com/Square-Schnei.../dp/B00CONA1OQ

If you have a lot of lightning around but like to use the big 12kW US shore power 120/240V 50A then I recommend this unit which is also a management system that will only pass good power: https://www.amazon.com/gp/product/B003AN1UA8
(It has a contactor). I have that as well for use at our marina slip in Florida. There’s a thread about that as well.

I also recommend another AC surge suppressor at the AC distribution panel. That is called the level 2 protection. It handles whatever is left over after the suppressor at the shore power inlet does most of the work there, but in addition, it handles surges coming from branche circuits when a surge comes from appliances like A/C units, refrigerators etc. either by their normal operation or when exposed to a near lightning strike.

There’s also a level 3. This would be a power outlet or power strip with a built in suppressor. Or even these small APC UPS units. You would use those for electronics like TV’s, computers etc.

We are headed to Panama, hence my intense focus on this project! I will review the DC wiring diagram and supressor, thanks for sharing!


Regarding AC, IF we are not at marinas is this as large a concern? I recently added a Galvanic Isolator at the shore inlet connector as well as a dedicated breaker on the shore power line prior to it entering the distribution panel.


Thanks so much!

[s/v Jedi]

Originally Posted by captNordy

Yes, there is another bolt coming out of fiberglass where the prop shaft enters the engine room. Presumably, the aft thru hulls, diesel tank, etc. link to this bonding bolt, and the fwd thru hulls, water tanks, mast and chainplates rout through the bolt at the mast base.


I will verify all this with continuity meters. However, you mention only having chainplates, mast, and coax surge on the fwd bonding bolt, but that would then mean a long cable run for the fwd thru hulls, and water tanks back to the rear bonding bolt, which is not ideal...





We are headed to Panama, hence my intense focus on this project! I will review the DC wiring diagram and supressor, thanks for sharing!


Regarding AC, IF we are not at marinas is this as large a concern? I recently added a Galvanic Isolator at the shore inlet connector as well as a dedicated breaker on the shore power line prior to it entering the distribution panel.


Thanks so much!

Disconnecting from shore power is the best defense against surges. The problem is that for places like Panama, Florida, you basically can never have shore power because lightning is a daily occurrence.

In you situation (and we have been in Panama for 10 years) I would want an isolation transformer with surge protectors at both the primary and secondary sides. It would be well worth the investment.

I have a basic diagram for that, you can find it by searching for threads started by me with the word diagram in the subject

[captNordy]

I'll search on the 'diagram' from you now.


One thing I'm still uncertain on is the best practice for wiring bonding wires. I have two bolts (one under mast, and one at prop shaft entry in engine bay) that are my bonding bolts. There is only one wire coming in to each bolt, yet I have lots of water, diesel, thru hulls, rudder shafts, etc. all bonded.



Am I to assume that bonding wires, unlike DC circuits, can just daisy chain off other bonded items vs having a 'bonded bus bar' where each bonded item terminates? That is to say, the back stays are bonded to the rudder shaft, which is bonded to the diesel tank, which is bonded to the thru hull, which then terminates at the bolt in the engine room.


Also, when 'earthing' things like the Victron MPPT controllers, that is the same as 'bonding', correct? The case goes to the bonded circuit via the nearest other bonded item. Same with your DC supressors in your diagram, they don't need to go directly to a 'bonding bus bar', but just to the nearest bonded item?


This seems a bit counter-intuitive since I read that during a lightning strike you want as direct a path as possible to the bonded item, so seems each item would have a direct run and there would be a 'bonding bus bar' that everything would terminate and then that bus bar would connect to the bonding bolt.



Thanks for the help as I try and learn more about the nuance of bonding circuits. Just trying to understand the larger picture. For example, your VHF/AIS wiring diagram thread you say to only have coax supressor, chain plates, and mast terminate at the dynaplate you show. If I only have those items on the bolt at my mast, that means I have several thru hulls that are fwd of the mast that would need to be bonded all the way back to the engine room, not the mast even though it is a way shorter run.

[s/v Jedi]

Originally Posted by captNordy

I'll search on the 'diagram' from you now.

One thing I'm still uncertain on is the best practice for wiring bonding wires. I have two bolts (one under mast, and one at prop shaft entry in engine bay) that are my bonding bolts. There is only one wire coming in to each bolt, yet I have lots of water, diesel, thru hulls, rudder shafts, etc. all bonded.

Am I to assume that bonding wires, unlike DC circuits, can just daisy chain off other bonded items vs having a 'bonded bus bar' where each bonded item terminates? That is to say, the back stays are bonded to the rudder shaft, which is bonded to the diesel tank, which is bonded to the thru hull, which then terminates at the bolt in the engine room.

Also, when 'earthing' things like the Victron MPPT controllers, that is the same as 'bonding', correct? The case goes to the bonded circuit via the nearest other bonded item. Same with your DC supressors in your diagram, they don't need to go directly to a 'bonding bus bar', but just to the nearest bonded item?

This seems a bit counter-intuitive since I read that during a lightning strike you want as direct a path as possible to the bonded item, so seems each item would have a direct run and there would be a 'bonding bus bar' that everything would terminate and then that bus bar would connect to the bonding bolt.

Thanks for the help as I try and learn more about the nuance of bonding circuits. Just trying to understand the larger picture. For example, your VHF/AIS wiring diagram thread you say to only have coax supressor, chain plates, and mast terminate at the dynaplate you show. If I only have those items on the bolt at my mast, that means I have several thru hulls that are fwd of the mast that would need to be bonded all the way back to the engine room, not the mast even though it is a way shorter run.

I really don’t know. We don’t even know what those bolts are, if they connect to something and what that is.

If the wiring is all original and from a reputable builder then you could assume it is okay, but does the builder state that the bonding system is designed to handle lightning strikes? If now then all bets are off the table.

If you would know exactly what you have then I could see if I can find some guidance from ABYC. I checked out install and found it exceeds ABYC recommendations so I know I have that somewhere, but this only makes sense when you know what you have.

I am against bonding everything to the same bonding system. Especially when they start connecting electrical systems to it as well.

[captNordy]

Understood, it is a '05 Tayana, so reputable on most aspects.

[s/v Jedi]

Originally Posted by captNordy

Understood, it is a '05 Tayana, so reputable on most aspects.

Yes, that should be good. The question is then what exactly these bolts are.

[s/v Jedi]

Save this before it magically disappears

[Hartleyg]

Just curious, Jedi - what voltage gas tubes are you using for your VHF radios coaxial protectors? They come in several voltages commonly - 90V, 260V and 330V seem to be common, but I'm sure there are others.


Hartley
S/V Atsa

[s/v Jedi]

Originally Posted by Hartleyg

Just curious, Jedi - what voltage gas tubes are you using for your VHF radios coaxial protectors? They come in several voltages commonly - 90V, 260V and 330V seem to be common, but I'm sure there are others.

Hartley
S/V Atsa

I must admit I don’t even know…. of course they don’t sell the ones I have anymore so no way to check other than physically… but I’ll be back with the boat in a week so I will be able to

[team karst]

25 Watts with good VSWR will result in about 35Volt rms on 50 Ohms. So, go low on the breakdown gas tube.